Because traditional brushless motors wind copper wires through slots in a laminated silicon-steel core, magnets passing by the lamination shoes have a greater attraction to the iron at the top of the laminations than to the air gap between the shoes. This uneven magnetic pull causes cogging, which increases motor vibration and noise.

In a slotless, brushless design, the motor's copper wires are wound against the laminations and held with adhesive. This design yields smooth rotation and virtually eliminates cogging.

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